I don't really have any experience with wind.
For privacy, I would choose something that could vine around some bamboo stalks or on a trellis. A big container on the floor with a trellis in it, and the trellis secured to the railings. Hyacinth beans perhaps, or a clematis (if you choose a clematis, you could still have a bean or nasturtium in the pot for the first year). If you choose a clematis (or another type of perennial), you would have to shelter it a bit in the winter (many posts on here about that). On the long railing, you could put window boxes. For higher plants, you would need some deep window boxes, otherwise most things would just tip over.

Other ideas for annual climbers: Black-Eyed Susan, Cardinal Climber, Morning Glory, Scarlet Runner Beans and Spanish Flag